Help me with my attack

I haven't gotten into this line of the KID before, but I know that black attacks the kingside while white attacks the queenside.

I noticed that white had better development and activity all game, and my only compensation was my attack. Since it didn't work out, I ended up with a lot of pressure where I played less than optimal moves.

I think your overall evaluation is correct : once your kingside attack came to an end, you're left with an exposed king and white takes the upper hand.

So the first question is : can you improve your kingside attack ?

My feeling is that 16...g3 17.Nf3 helps his defence a lot, as it's not clear how you can get to his king after this. So maybe 16...f3 is worth a look ? (on 17.g3 h4 opens some lines).

25...Nxd3 looks strange too : why trade an attacking piece and bring his queen on the excellent d3 square, where it defends along the 3rd rank and hits the h3 bishop with tempo ? There's probably a better move at this point too.

And yes, in the final position 43...Re8 and it's still a fight !

I think the problem started on move 8. Whenever you move your pawns, especially in a d4 opening, you always have to consider what it does to the activity of your bishops. In this case, you're trapping your own fianchettoed bishop with d5 which is funny because if you fianchetto a bishop you should try your best to open that diagonal. Notice how for the rest of the game that thing on g7 would be useless(unless white blunders positionally) Sure it also traps his light colored bishop but white has the move c5! later on to free it.
Ne8 only made it worse, after closing the diagonal with d5 you could have at least gotten some compensation by having a knight in a closed position,  but you retreated it without thinking of where it would go after (after Ne8, the only square it can go to actively participate is back to f6)-- its sole purpose was to push the f5 pawn which was okay if you had the right plan in mind which was if f5, exf5 gxf5 followed by e5! by black opening the h8-a1 diagonal... but then again if you had avoided closing the position in the first place, you wouldn't have had to push through with this plan. You basically commited suicide after f4.
after f4, white prepares c5!, activating his light squared bishop and comes up positionally winning (superior bishop)
Instead of 11...g5, I would have played 11...c5 on move 11 to prevent him from activating his bishop-- playing for equality. (11...c5! equalizes the position and suddenly the game is all about manuevering knights.)

12. Na4!(preparing c5) h5? (the attack will not yield anything because of the lack of mobilized pieces on the kingside, by the time you get to activate your own pieces, he would have played c5! and started his own queenside attack... also notice he could just ignore your kingside attack and close the kingside pawns)

13. c5! g4?!(dubious because in this position white would have liked to go back to d2 to participate on the queenside attack, white should know that your attack would have nothing)

14. Nd2 Qg5? (probably your idea was f3, but white is not forced to go gxf3??, he would do g3! and completely stop your attack. Better was to find a way to get your dark squared bishop/knights into the queenside defense)

15 cxd6?? Nxd6 (this surrenders white's attack. all of a sudden white has no counterplay and all the advantage is with black., better was something like Nc4, keeping the attack and preparing to get to a5 where c6! will be very strong. Note that black would not be able to stop Na5 later on with b6 because it would create a hole on c6 which will be exploited after a few moves)

16. Bb2? g3! (a move ago, before Bb2?, g3 would have been dubious because of the possibility of discoveries on the h6-c1 diagonal. But after Bb2, it allows black to get a scary initiative with g3!)

17. Nf3! gxf2?? (Nf3 was one of the many good moves for white to defend, but gxf2 is just bad. You see, when you are attacking in chess, you have to PREPARE it. Look at the position, how many pieces are participating in the attack? One; your queen. The rook on f8 will not be actively participating after gxf2 because notice how after gxf2, it blocks the f-file because your f4 pawn will be immobile. To make it worse, that one piece that is participating in the attack is not actually doing anything significant. gxf2 was a clear blunder. In case you didn't know, the point of g3 was to try to TRICK white into taking on g3 and NOT the other way around. Compare the position if white had taken on g3 (ex. hxg3 fxg3!, opening the f-file and black has an attack) and if black takes on h2 or f2. If black takes on h2 or f2, his rook on f8 would be useless. Thats why, why did you do gxf2?? its as if saying that you played g3! because it 'looked good' and without any solid ideas/plans behind it... you completely disregarded what was supposed to be your plan here.. by the way, it also creates some ideas for white to switch over to the kingside to attack now... sorry if I sound mean but gxf2 is just THAT bad... I don't know if you realized this but gxf2 completely gave the game away... after gxf2 the best you should get is a draw, after gxf2 you might as well resign.

18. Kxf2 Qg6 (now what? since you blundered last move you have no attack at all and white can just wait.. you would get nothing in return..)

19. Rac1?! Ne8?? (Probably better for white was Rec1 since the e-file rook is not as active in the queenside attack. Black blunders again with Ne8?? You have to realize early on if you have an attack or not. trying to herald pieces to the kingside would be useless especially after that gxf2 blunder. Maybe it would have garnered some counterplay if you hadn't done the gxf2 blunder... Your plan should be to play for a draw in this position, you should be putting your pieces to the queenside for defense, not retreating them from the queenside!

20. Nc5?! Ndf6??  (Nc5 offers a trade, it's not that bad but usually white would want to avoid trades in a position where he has more space and the attack. Ndf6?? was yet another blunder. You again try to put a piece in the kingside hoping for some miracle attack but nooo. you don't realize that you have nothing in this position. you should have doen Nxc5! followed by defending the e5 pawn where black at least would have improved a bit... after Ndf6?? you should resign. Your knight on e8 will have to be moved again and you're wasting too much time playing with that useless e8-knight.  It also allows Nxe5 by the way.

21 Nxe5 Ng4! (finally a good move by black. black finally realizes that he needs more space and needs to trade; he also finally realizes that his attack has come to nothing and that he must create ways to get to the queenside; he also finally realizes that his knight is completely bad and its good to trade bad stuff for good stuff. NO CREDIT if this wasn't what you were thinking though.

22. Kg1?? Bxe5! (taking with the bishop was very strong in my opinion. Black finally realizes and admits that his bishop was bad and it's good to trade it for a superior minor piece. NO CREDIT if this wasn't what you were thinking though)

I'll stop here because the rest of the game was a flop.  That was pretty much all the instructive parts. After 22. Bxe5! Black is surely winning and its a matter of not being a noob/idiot and giving the win away.

Its good that you are starting to formulate long-term plans in chess. It was a good game however the plan you had in mind was inferior in my opinion (I explained why above)....

In case you don't know I don't play chess here anymore because of the lagg, and I have improved ages since I've last played here so please ignore the rating lol.